Rodgers focused on California's groundbreaking initiative to reduce greenhouse gas emissions to 1990 levels by 2020, a cut of about 30 percent from current levels.

Experts have established detailed plans on how to reach the target reduction, with a large focus on transportation, although the California Air Resources Board has yet to embrace a comprehensive plan that will get anywhere close to the goals it is charged with meeting.

Cal Broomhead, climate programs manager at the San Francisco Department of the Environment, spoke on local green efforts. He praised the city for keeping the same levels of greenhouse gas emissions since 1990 and its continued use of the "Fab 3" composting and recycling program.

Broomhead also stressed the importance of furthering environmental education efforts: "Through education we can get people to adopt pro-green technologies and behaviors. Once you have the last remaining stragglers, then you can require them to participate through law."

Comments, ideas, and submissions for Green City, the Guardian's weekly environmental column, can be sent to news@sfbg.com.